1. Field of the Invention
The present invention relates to a flexible molded foam. More particularly, it relates to a flexible molded foam which comprises a surface layer comprising a linear polymer, an intermediate reinforcing layer comprising a three-dimensionally crosslinked polyurethane and a core layer composed of a semi-rigid polyurethane foam, and a process for the preparation of such a flexible molded foam.
2. Description of the Prior Art
A flexible molded foam comprising a core layer composed of a polyurethane foam has been used as a cushioning material. A surface skin layer has been attached to said core layer as an outer decorative material, and is widely used as an interior decorative material in, for example, an automobile or other vehicle.
One type of decorative material is a product obtained by first preparing an outer decorative material as a surface skin layer by a separate step of vacuum molding or the like, and then attaching this outer decorative material to a polyurethane foam. Another product is obtained by attaching a coating film as a surface layer to a self-skin-foaming flexible foam which is a special polyurethane foam.
However, it is very difficult to first prepare an outer decorative material as a surface skin layer by a separate step because, due to the properties of this outer decorative material, it is very difficult to form a fine surface pattern, such as a leather or texture-embossed pattern or a stitched pattern. Also, the self-skin-forming flexible foam is low in foaming ratio and has a high density. Therefore, the resulting foam has a heavy weight and lacks flexibility and, accordingly, it is not preferred from an economical viewpoint. Moreover, strict manufacturing conditions should be utilized for obtaining this foam.